Page fusion cause Guru Meditation on Windows 7 x64

Description

When creating at least two VMs with Windows 7/2008 x64 and having them running at some point together, they always end up in Guru Meditation after doing random things (logoff the user, lanch applications, crash others).
There is obviously some memory sharing/corruption issues.

The guests have the 4.2.4 additions installed and I can reproduce this crash at will on a Windows 7 x64 and Linux Debian based x64 aswell.

I have tried with and without large pages on.
This bug was already in previous versions (at least from 4.1.x).

Some update on this :
I cannot recreate this bug under Ubuntu 12.10 with Gnome3.
I cannot recreate this bug under Debian Wheezy with testing packages.

I can recreate the behaviour (but not a guru meditation) under Windows 7 64 bits SP1 host with two Windows 7 64 bits SP1 guests.

What I did in order :

Created 2 VMs

Changed RAM to 1024Mb and gave more than one core

Installed Windows 7 (rebooted several times)

Installed the 4.2.4 additions

Rebooted after additions install

Shutdown of the VMs.

Take a snapshot (this bug caused my VDI to get corrupted several times which stopped windows to boot)

Enabled page fusion on both VMs.

I have then started both VMs and simply waited for them to boot.
The first one was extremely slow to boot, much more than usual when I boot 2 Win7 VMs
The second actually made it and rebooted at some point during the boot.

Once both VMs were booted, they frooze from time to time for while, programs like IE, Notepad and Explorer got display artfacts (not displaying a part of the window was always happening) until they both crashed with a BSOD.

Finally, the VM 02 gave up, explorer crashed with a memory read/write error and went berzek by constantly sending garbadge on the vNIC.

You will find two zips (VM01.zip & VM02.zip) both with the vbox.log aswell as the minidumps from the BSOD.
You will also find a screenshot of VM 02 with the memory error.

Note that if I shutdown both VMs, restore the snapshot to recover from the VDI corruption, disable page fusion then reboot, everything is fine. No part of the behaviour described above appear.